Recently, in the field of television receiver for household use for example, a display device represented by a liquid crystal display device that includes a liquid crystal panel as a flat display part having numbers of features such as decreased thickness and decreased weight in comparison with a conventional cathode-ray tube, have been mainstream. Such a liquid crystal display device is provided with an illumination device (backlight) that emits light and a liquid crystal panel that displays a desired image by functioning as a shutter against light from a light source provided to the illumination device. And in the television receiver, information such as characters and images included in the video signals of the television broadcast are displayed on the screen of the liquid crystal panel.
Furthermore, as the aforementioned illumination device, an edge light type or a direct type backlight device is provided in which a linear light source constituted of a cold-cathode tube or a hot-cathode tube is placed on a side of or below the liquid crystal panel. However, the cold-cathode tube such as described above and the like contains mercury, resulting in difficulty in, for example, recycling the cold-cathode tube to be disposed of. In view of this, an illumination device whose light source is light-emitting diodes (LEDs) in which mercury is not used has been developed.
Further, as a conventional liquid crystal display device, a product using an illumination device including a plurality kinds of LEDs has been proposed as described in JP 2000-275636 A. In other words, in this conventional liquid crystal display device, first and second LEDs for emitting monochromatic lights of blue and red are provided, and a phosphor film is placed on the front face of the first LED so as to generate a green light from the blue light from the first LED. And this conventional liquid crystal display device obtains white light by additive mixture of color stimuli of blue light, green light and red light, and allows the white light to enter the liquid crystal panel.